This capacitive sensor that operates with a high frequency oscillator was found in Radio Electronics from the 90's. The circuit operates around 300 kHz.
We found this circuit in an old neon lamp application manual. The circuit stores a call. The...
This isolation circuit for audio signals was found in the August 1992 issue of Radio Electronics...
This fuzz uses only one transistor that can be the BC548. Signal input and output cables must be...